NASA has revealed a scheme aimed at averting extinction from “planet killer” asteroids attributed to the demise of dinosaurs that occurred some 66 million years ago. The National Preparedness Strategy and Action Plan for Near-Earth Objects (NEOs) and Hazards released recently gives quite a comprehensive framework to address hazardous NEOs.
There’s no urgent danger, but that doesn’t mean there will be a respite in practice; NASA is preparing for contingencies like, for example, “1,000 spacecraft” all waiting in orbit, ready to launch on the order to go and intercept and nudge a big asteroid headed towards the Earth.
In case the asteroid cannot be moved out of the way with sufficient time left, a last resort option that NASA may consider is nuclear response which is similar to the scenario in the 1998 film, “Armageddon”. An especially tempting application would be to destroy or redirect an enormous asteroid within several months' flight time of the earth using nuclear devices, eliminating global catastrophe.
These plans also reflect the alarming fallout from an asteroid impact, which has motivated NASA’s contingencies. In this case, if a planet killer asteroid like the one that served as the cause of the Chicxulub impact happened to collide with the earth, there would be extreme heat generated and erosion of matter to a vapor state and dust clouds obscuring the sun's rays causing an ‘impact winter.’ The simple fact is that this would lead to mass extinction events which emphasize the importance of the agency’s planetary defense programs.